• Archives of Pharmacal Research
• /
• v.16 no.2
• /
• pp.152-154
• /
• 1993

By using N-bromophthalimide (NBP) as halonium ion source for the Hofmann rearrangement, a series of primary amide could be ocnverted to the corresponding cabamate in excellent yields. So NBP was throught to be very effective and practical halonium ion source for the Hofmann rearrangement.

• Archives of Pharmacal Research
• /
• v.17 no.1
• /
• pp.39-41
• /
• 1994

Various N,N'-disubstituted ureas 5 were easily prepared from the corresponding primary amide 1 by tratment with N-Bromophthalimide $(NBP)-AgOAc-RNH$_{2}$ 4 in dry N,N-dimrthylformamide (DMF). This reaction envolved the intemediate formation of isocyanate 3 from amide 1 via Hofmann rearrangement by treatment with AgOAc and NBP and nucleophilic addition of amine 4 to this isocyante 3. This method is simple enough to be applied to the synthesis of various N,N'-disubstututed ureas scale conviently.

• Archives of Pharmacal Research
• /
• v.4 no.2
• /
• pp.137-139
• /
• 1981

Reaction of olefinic acids with N-bromophthalimide in dry N, N-dimethylf-ormamide at room temperature gives bromolactones in good yields.

• Archives of Pharmacal Research
• /
• v.6 no.1
• /
• pp.45-53
• /
• 1983

Novel halactolactonizations using NBS (2), NIS(3), and NSP(4) in dry DMF were found to be the most reasonable and efficient procedures. The participation of X as the cylization initiator could be clarly rationalized by experimental results and the regioselectivities of formed halolactones were reasonably elucidated by weakly bridged carbonium ion intermediate.

• Korean Journal of Clinical Pharmacy
• /
• v.8 no.2
• /
• pp.133-138
• /
• 1998

Phthalimidyl ester of ceftezole (CFZ-PT) was synthesized as a prodrug by esterification of ceftezole (CFZ) with N-bromophthalimide. CFZ-PT was more lipophilic than CFZ when the lipophilicity was assessed by partition coefficients between n-octanol and water at various pH. The pharmacokinetic characteristic of CFZ-PT and CFZ preparations were compared following oral administrations of these compounds to rabbits. CFZ-PT is expected to be metabolized rapidly to CFZ in the body. The metabolism process appears to be hydrolysis of the ester to CFZ, the parent drug of CFZ-PT. In vivo metabolism of CFZ-PT to CFZ was confirmed in rabbit by HPLC analysis. CFZ concentration in the serum samples taken after oral administration of CFZ-PT(equivalent amount of CFZ) were released and higher than those of CFZ. Oral bioavailability of CFZ-PT was 1.9 fold higher than at of CFZ in rabbits because of enhanced lipophilicity and absorption. Finally, it was concluded that CFZ-PT appears useful as a prodrug of CFZ to improve the oral bioavailability of CFZ.